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A modified Mojonnier method, and two lactometer methods, each designed to give rapid approximations of total solids content of milk from individual cows, were compared with the standard Mojonnier method. Each of the rapid methods underestimated a high solids content and overestimated a low solids content. The Cenco Rapid Moisture Tester proved to be accurate but no more rapid than the standard Mojonnier method.

Five rumen-fistulated wethers were dosed intraruminally with a single dose of 75Se-selenomethionine, and the rumen liquor was collected after various time intervals and separated into bacterial, cell-free, and protozoa plus plant material fractions. Maximum 75Se activity in rumen fluid was observed 2 h after labelled selenomethionine was administered. At 6 h post-dosing, 50% of the rumen liquor label was in the bacterial fraction, decreasing to 20% at 96 h. The majority of bacterial 75Se activity was found to be protein-bound. In a second experiment, five wethers were given 75Se-selenomethionine intraruminally, and 2 h later ruminal bacteria were isolated for identification of selenocompounds in the bacterial protein. Paper chromatographic separation of protein enzymatic hydrolysate showed the presence of selenocystine, selenomethionine, elemental selenium, and 40–50% 75Se activity as unidentifiable components. In an in vitro study, 75Se-selenomethionine was incubated with a rumen bacterial fraction, and ion-exchange and paper chromatography were used to identify selenocompounds formed. The results indicated that 75Se-selenomethionine was metabolized by the bacteria to 75Se-selenocystine, with both selenoamino acids incorporated into bacterial protein. With ion-exchange chromatography, unless carrier selenomethionine was added, 75Se-selenomethionine was degraded and a high proportion of 75Se activity remained on the column.

Chromic oxide (Cr2O3) in paper pellets was used as an indicator for digestibility studies with four Holstein-Friesian cows fed rations composed of different roughage to concentrate ratios. Cows A and B received one pellet, or 3.46 g of Cr2O3, whereas cows C and D received three pellets, or 10.38 g of Cr2O3, daily.Recovery of Cr2O3 in the feces varied from 84 to 103% for animals A and B and from 92 to 95% for animals C and D. The coefficients of apparent digestion of dry matter were lower (P 2O3 method was used instead of the conventional method. When samples were taken at 0500, 0900, 1300 and 1700 hours, the Cr2O3 method gave average estimates of digestibility for animal pairs A, B and C, D that were 94.2 and 97.5% of those obtained by the conventional method. Standard deviations for both the Cr2O3 and conventional methods were relatively high.Excretion patterns of Cr2O3 were not signicantly correlated with those of crude protein, phosphorus and calcium. The average concentrations of crude protein, phosphorus and calcium in compounded feces samples collected at 0500, 0900, 1300 and 1700 hours were 101.3, 100.6 and 96.7% of those in samples of the total excretions.The daily administration of 10.38 g of Cr2O3 at 0900 hours for eight days, and the collection of fecal grab samples at 0500, 0900, 1300 and 1700 hours daily during the last five days seemed satisfactory for estimating apparent digestibility of dry matter.

Five experiments involving 90 newborn colostrum-deprived pigs were conducted in an attempt to develop a method of rearing applicable in a non-isolated environment. Immune globulins, prepared by ammonium sulphate fractionation of porcine serum, and comprised of a mixture of approximately 75 per cent γ-globulin and 25 per cent β-globulin, were administered orally or parenterally in varying amounts and for varying periods of time. In two experiments porcine albumin, in serum or in a semi-purified solution, was provided in addition to the immune globulins. The distribution of serum proteins in the pigs was studied from birth to 12 weeks of age by paper strip electrophoresis.Parenteral administration of immune globulins did not provide an effective passive immunity, nor did oral administration for 1 day post-partum. A marked improvement in survival occurred when oral administration was continued for 5 days, and it was further found that this treatment provided apparently complete protection against infection during the 5-day period of administration. Albumin appeared to further improve survival.These results, together with the relatively poor survival obtained with positive control pigs (nursed 24 hours) suggested a continuing need for a supply of immune globulins in the lumen of the intestinal tract. Presumably these globulins were active as coproantibodies.The percentage survival in pigs weighing 3 pounds or more at birth was substantially higher than in smaller pigs. Mortality in these experiments was usually attributable to colibacillosis.Serum immune globulin levels at 2 days of age in the artificially reared pigs were elevated in proportion to the amount of globulins given. The effect of albumin was to create a serum protein pattern resembling that of suckled pigs. A marked decline in γ-globulin levels from 2 days to approximately 6 weeks was observed.

This is the second in a series of reports on the growth, feed intake and digestibility responses of growing swine (50 to 110 pounds) involved in a 2 × 2 × 2 × 2 factorial test of the effects of wheat bran, pelleting, antibiotics and type of protein in the ration. Discussion in this paper was restricted to those factors affecting the responses to the inclusion of wheat bran.With approximately isocaloric diets the inclusion of 10 per cent bran resulted in a general increase of 6 per cent in feed intake (P =

Two experiments were carried out with Hereford and Aberdeen Angus steer calves to study the influence of feeding concentrate and hay in the ratios of 1:2, 1:1, 2:1; of feeding the concentrate in the pelleted and the ground form; of pelleting the entire ration; and of feeding the ration ad libitum and according to the body weight of the animal. All comparisons were not made in each experiment. Each lot in each experiment was made up of four Aberdeen Angus and seven Hereford calves. All animals were fed individually. Only the data obtained between 500 and 900 lb. body weight were considered in this paper. The animals were slaughtered as they reached 900 lb. and certain carcass data obtained.The steers fed concentrate to hay in the ratio of 1:2 made smaller daily gains, required more feed (T.D.N.) per unit of gain, had lower dressing percentages, and had less fat in their 9-10-11 rib sections than those fed rations with ratios of concentrate to hay of 1:1 and 2:1. The steers fed the 1:1 ratio made significantly smaller daily gains and required more feed per unit of gain than those fed the 2:1 ratio of concentrate to hay, but were not different in dressing percentage or percentage fat in the 9-10-11 rib sections.There were no significant differences between those steers fed their concentrate in the pelleted or ground forms. In one experiment, pelleting the entire ration resulted in significantly lower daily gains than pelleting only the concentrate and feeding the hay chopped, but in the other experiment there were no differences. Pelleting the entire ration resulted in no significant differences in feed efficiency, dressing percentage, or carcass grade. Limiting the daily consumption of feed to predetermined amounts dependent upon body weight did not influence efficiency of feed utilization or carcass characteristics as compared to ad libitum feeding.The Hereford steers that were fed in these two experiments made greater body gains per unit of feed consumed but had less body fat and in one experiment had lower grading carcasses than the Aberdeen Angus steers.

A swine feeding trial, of 2 × 2 × 2 × 2 factorial design, involving 64 pigs (32 gilts and 32 barrows) weighing initially 50 ± 2 pounds and fed to a final weight of 110 ± 2 pounds was carried out. The dietary variables were meal vs. pellets, 0 vs. 10 per cent wheat bran, mixed animal-plant vs. all-plant origin protein supplement and 0 vs. 33 p.p.m. of an antibiotic mixture (penicillin, streptomycin and chlortetracycline). Weight gains and feed intakes were recorded bi-weekly and a Cr2O3-marker digestion trial was imposed on 32 pigs during the feeding test.The results revealed distinct interrelationships among all four experimental variables that prevailed through to the highest order statistical interaction. Consequently discussion in this paper was restricted to those factors affecting the responses to pelleting.On the whole there was no advantage due to pelleting. However, in the absence of bran and antibiotics, and particularly when no animal protein was involved, pigs fed pelleted feed gained faster and had better feed efficiency. Pelleting was found to increase dry matter and energy digestibility when no bran or antibiotics were included in the diet. Conversely, the inclusion of either bran or antibiotics was as effective as pelleting. It is postulated that bran and antibiotics were effective by reason of their effects on the physical nature of the ingesta and on the microbial population of the gastrointestinal tract.